This invention relates to an improved switch terminal and an improved connector with such a switch terminal.
Generally, with respect to a connector used for interconnecting wire harnesses, a pair of female and male housings are fitted together so as to connect metal terminals, received in these housings, together. In order to maintain electrical connection between these metal terminals, a lock member is provided between the two housings to prevent them from being disengaged from each other. In order to detect the fitted and locked condition of the two housings not by a lock sound or a visual inspection but by electrical means, there has been proposed a method in which a switch terminal is received in one of the two housings, and is adapted to be closed upon complete fitting between the housings.
FIG. 12 shows one example of such switch terminal (Japanese unexamined Utility Model Application No. 55-51731) in which a pair of main contact pieces d and d, which are urged by springs c and are short-circuited together by a short-circuit piece b before a test plug (not shown) is inserted into an insulating casing a from an opening a1 thereof, and a pair of auxiliary contact pieces e and e, which are contacted with the test piece before the main contact pieces d, are provided on inner surfaces of the casing a.
FIG. 13 shows another conventional example in which a switch mechanism is constituted by a fork-like contact piece f, having contact portions f1 and f1 of a bifurcated configuration, and a spring contact piece g having contact portions g1 and g1 of a saddle-like configuration for contacting with the contact portions f1 and f1 of a bifurcated configuration. The two contact pieces f and g are disposed at respective positions offset from the center of an insulating housing h in opposed relation to each other, and a central hole i is formed through a central portion of a front end of the insulating housing h, and a plug terminal (not shown) is passed through the central hole i to be engaged with the saddle-like contact portions g1 and g1 of the spring contact piece c so as to open and close the above switch mechanism.
In the above conventional switch terminals, the springs are used to apply a contact load to the contact portions (FIG. 12), and the fork-like contact piece and saddle-like spring contact piece of different shapes are used (FIGS. 13a and 13b). Therefore, the number of the component parts is large, and the constructions are complicated, and much time is required for the assembling, thus posing a problem that the operability is worse.